Last removing machine



June 4, 1963 s. HAWKES LAST REMOVING MACHINE 3 Sheets-Sheet 1 Filed Dec. 11, 1961 June 4, 1963 s. HAWKES 3,091,787 LAST REMOVING MACHINE Filed Dec. 11, 1961 3 Sheets-Sheet 2 L Ifil 39 June 4, 1963 s. HAWKES 3,091,787

LAST REMOVING MACHINE Filed Dec. 11, 1961 3 Sheets-Sheet 3 3,ll1,787 LAST REMOVING MACHTNE Sidney Hawires, Rushden, England, assignor to Fred Hawkes (NIV. Engineers) Limited, Rushden, England,

a British company Filed Dec. 11, 1961, Ser. No. 158,181 Claims priority, application Great Britain Dec. 15, 196i) 7 Ciaims. (Cl. 1215.1)

This invention is concerned with last removing machines such as are used in the boot and shoe industry for separating a fabricated or partially-fabricated shoe (or similar item of footwear) from a last on which it has been made. All such articles will, for convenience, hereinafter in this specification be assumed comprehened in the term shoe.

Conventional machines of this character are provided with an upstanding jack pin on which the last, carrying the fabricated shoe, is mounted with the pin entering the hole provided at the upper side of lasts for support in this way during the actual manufacture of the shoe thereon. The machines for this purpose also include a thrust device (which can take various forms) which is then arranged to be operated to engage at the back of the shoe heel and to lift it so that the shoe (which is, of course, sole upwards in this condition) will be pushed oi the last.

Various methods of engaging the shoe for this purpose have been used in the machines. In some cases a rubber pad is applied at an angle against the maximum curvature of the shoe heel, whilst in others a roller is brought into contact wtih the shoe at a similar position with the object of rolling the shoe olf the last.

In practice it is found that the distance between the jack pin hole and the ultimate rear curved end of the last varies from last to last. To cater for this it has been necessary in the past, to equip the last removing machine so that the position of the jack pin relatively to the stripping member, i.e. the pad or roller, can be adjusted by the operator and set ready in the adjusted position for each last variation. This, however, is not only time consuming and troublesome, but is imprecise inasmuch as the actual variation of the aforesaid distance can only be generally judged by the eye, so that the setting must always be a rough one. On account of this, experience teaches that the uppers of the shoes are frequently damage because of the improper application of the stripping member.

Thus, conventional last removing machines are generally fitted with a hand wheel to enable the operator to adjust the jack pin fore and aft to compensate for major variations of measurement between the jack pin hole and the rear extremity of the last. Over-adjustment away from the operator often results in a stoppage or breakage because the working pressure between the rear end of the shoe and the pad or roller is too great, whereas underadjustment towards the operator results in slip between the pad or roller and the rear surface of the shoe upper, with consequent damage to the material of the latter and loss of time.

The machine which forms the subject of the present invention has been devised with the object of overcoming these various shortcomings and comprises a last support, an associated movable stripper device, means operable to move said last support to apply the heel of the lasted shoe against said stripper device, and means re sponsive to contact pressure between the lasted heel and stripper device to operate the latter so as to slip the shoe from the last.

Thus, in an advantageous form themachine comprises a last support, a stripper device normally parted from said last support and a lasted shoe thereon, means for 3,091,787 Patented June 4, 1963 producing relative closing movement between the last support and stripper device, and means responsive to a predetermined contact pressure between the stripper device and a lasted shoe on the last support to provoke a movement of this stripper device transverse to the direction of said closing movement to slip the shoe from the last.

We thus are afforded, in effect, an automatic jacking system which automatically ensures a correct degree of pressure application between the shoe and the stripping device, irrespective of variations in the size of shoe and the dimensions of the lasts. Further, the slipping movement cannot start until correct pressure has been established between shoe and stripping device and danger of faulty manipulation of, and damage to, the shoe is precluded.

By virtue of these arrangements, when a last to be slipped is moved against the stripping device, in a motion which can be brought about by various pneumatic, mechanical, or other means and can be initiated by the hand or foot of an operator or by some automatic control, the remainder of the shoe-removing operation takes place automatically and in self-adapting fashion, so that the shoe is engaged and removed from the last under the optimum conditions, irrespective of the distance between the jack pin hole and the ultimate extremity of the heel of the shoe.

The required automatic response to bring about the actual shoe slipping can be implemented in various ways, for example by electrical switch means, by the operation of air valves controlling the stripping device, and so on.

In one convenient form, the stripper device has a part which is yieldable under the contact pressure with the lasted shoe, thereby to actuate a means to provoke a movement of this device as a whole transversely to the direction of closure movement between'it and the last support.

In pursuance of this last-mentioned arrangement, the stripper device may comprise an upwardly-movable head assembly which includes a pivotally-mounted stripper member which will yield and pivot relatively to the remainder of the assembly, to cause operation of means producing the upward movement referred to.

The stripper member referred to will best comprise a pad of rubber or other resilient material which will grip but not damage the shoe upper when they are in tight engagement, and this pad may itself be hingedly carried by a support member and urged outwardly from the latter by spring means. Advantageously the support member, and hence the stripper pad holder, can be set at an adjustable angle to the vertical, e.g. by set screw means. This allows for the selection of the optimum angle of engagement between the stripper member and the shoe heel, to cater for example for heels of different back curvature.

A predetermined degree of pivoting of the pad holder on its support member, under the pressure of the lasted shoe presented to it, can then be arranged to operate trip means, as indicated above-conveniently an electrical switch or an air valve, to initiate the upward movement of the strippermember. T

In the last mentioned case, the trip means triggering the last removal is indicated as carried by the stripper device. It is to be appreciated that it could instead be carried by some yielding means associated with the last support.

Referring now to the initial closure of the lasted shoe and the stripping device, it will be realised that this can be brought about in various ways. It has however been found very effective to use an arrangement in which the last support is mounted inthe machine so as to be pivotable to close a last thereon against the stripper device, and said last support is movable through a cam or wedge transmission to produce this pivoting movement.

spams? By using a cam or wedge to pivot the last support, it

is readily practicable to carry the lasted shoe progressively towards the stripping device, and apply it against the stripping member of the latter with a uniform pressure, irrespective of the distance between the last jack pin and the back of the shoe.

In one arrangement, the last support includes an upstanding post which is f-ulcrumed in a main frame of the machine and, at its lower end, carries a part moving over a cam or wedge surface which is movable by an operating means so as to swing about a remote pivot. Such remote pivotal mounting of the cam or Wedge provides for a very smooth and sensitive swing of the last support. As indicated the cam or wedge can be operated in various Ways, e.g. by a hand lever, foot treadle or by a pneumatic cylinder or a hydraulic cylinder under foot or hand control of an attendant.

It has, however, proven very satisfactory to use air (or, it could be, hydraulic) means to operate all the moving parts of this machine, and in one version the machine includes a pneumatic operating system which comprises a first air. cylinder to pivot the last support and cause a lasted shoe to be closed against the stripper device, a second air cylinder to move the stripper device to slip the shoe from the last, a mechanically-operable valve controlling the air supply to said first cylinder, and a solenoid valve operable in response to a predetermined pressure between the shoe and stripper device to open the air supply to said second air cylinder.

A form of last removing machine is illustrated in the accompanying drawings, in which:

FIGURE 1 is a perspective illustration of the complete machine,

FIGURE 2 is a side view of the same with a vertical section through the main frame housing.

FIGURE 3 is an enlarged side elevation of the head assembly of the machine, with part in vertical section, an

FIGURE 4 is a diagrammatic illustration of the stripper head assembly in association with the pneumatic operating means of the machine. I

The machine illustrated comprises a hollow main frame 1 which serves to house the operating parts of the machine and is shouldered at its upper part into a rear shelf-forming portion 2 having a boss 3 through which passes a plunger ram 4 carrying the stripper head assembly of the machine. The machine, in use, will be served by an attendant standing at the front side seen in the perspective view in FIGURE 1, and the head assembly is therefore positioned at about normal elbowheight.

This head assembly comprises a block 5 which is clamped on ram 4 by screws 6 and has a pair of lateral wings 7 on which are pivoted corresponding lugs 8 on a stripper pad supporting plate 9. As will be observed from the drawings, this plate is arranged at an inclination to the vertical ram 4, and this inclination can be varied, to suit particular requirements, by a set screw 10 threaded in the upper part of the plate 9 and bearing against block 5, and a lower adjusting screw 11 which is threaded into a forward extension piece of the block 5 and has its head bearing against the lower margin of plate 9.

This latter has lateral ears 12 serving to carry the pivot 13 for a stripper pad holder 14 which overlies the front face of support plate 9 and is normally spaced therefrom by compression springs 15. The outermost position of holder 14 is determined by a pin 52 on the holder, which engages in a slot in a link 53 on plate 9*. Inset into this holder 14, and clamped thereto by side cheeks 51, is a rubber stripper pad 16 having a rounded front surface.

It is to be noted also that the holder 14 carries a screwed stud 17 of adjustable length at one lower side, and this cooperates with the head 18 of a switch-operating plunger in a microswitch casing 19. The arrangement is that a predetermined swing of the holder 14 will operate the microswitch, which has been diagrammatically indicated at 2G in FIGURE 4.

Mounted between the side walls of the main frame 1 below a slot 21, extending across the width of the latter at its front shouldered part, is a shaft 22 which has rotatable thereon a casting 23 which includes an upstanding column 24 with a post 25 at its upper end supporting a jack pin 26.

The casting 23 at its lower side and at one end is formed with a depending tapered arm 27 with a pin 28 projecting from its lower end. The pin 28, or a roller thereon, is received in a cam slot 29 in the enlarged end of a further arm 30 which is pivoted at its other end, to a pivot pin 31 in a wall of the main frame 1. Pivoted at its lower end on a cross spindle 32 in the frame 1 is an air cylinder 34, the piston rod 35 of which is pivotally coupled by a yoke 36 to arm 30.

Another air cylinder 37 is mounted on a step bearing 38 on the aforesaid base of the main frame 1, and the ram of this cylinder forms an extension of the shoe removing ram 4. 1

A treadle 39, for initiating the various movements which occur when a shoe is to be removed, is cast in one piece with an arm 53 which is pivotally supported by a pair of spaced lungs 48 on spindle 32. At its rear end, arm 33 cooperates with the plunger 49 of a valve 40 controlling the air supply to cylinder 34 (see below).

The controls for the machine are diagrammatically illustrated in FIGURE 4, and it is to be noted that when the treadle 39 is depressed, the resultant movement of plunger 49 shifts over the valve member in valve 40 and so allows air to pass from a main airline 41 to the lower end of cylinder 34 and the piston rod 35 to be raised. Included in this line is an adjustable restrictor indicated at The line 41 has a branch 42 incorporating a slide valve 43 which is normally closed and is operablel by a solenoid in a casing 44. The solenoid windings are connected to the supply mains at 51 via the microswitch 20 of the head assembly, and the arrangement is that when the solenoid 44 is energised by closure of switch 20, it retracts the valve member in 43 and so opens the branch 42 to the underside of the piston in the air cylinder 37 to produce an upward stroke of ram 4.

A normal operation of the machine therefore proceeds as follows.

The operator in front of the machine places a last 45, carrying a shoe 46 to be slipped, sole-uppermost on the jack pin 26. 1 On depression of the treadle 39, the piston 35 of air cylinder 34 is operated and the arm 30 swings upwards to a small extent. The pin 28, bearing on the cam edge of slot 29, is consequently moved forwards a small amount and the post 24 accordingly rocked through a small angle to bring the heel 47 of the shoe 46 against the pad 16, i.e. into the position indicated in dotted lines in FIGURE 2, and then with a continuing pressure on this pad until the resistance of compression springs 15 is overcome and the microswitch 20 is closed. By virtue of the substantial length of arm 30 and the large curvature and vertical disposition of the cam edge 29, the movement of the heel 47 is small but continuous, and is possible to make the pressure-response of the microswitch very sensitive.

It will be noted that the part of the heel 47 against 7 which the pad 16 engages at this time can be adjusted by this opens valve 43 and sends an air impulse to cylinder 37, so causing an upthrust of ram 4 and a lifting of the complete head assembly, including the pad 16. The post 24 and last 45 remain stationary (since air continues to be applied to cylinder 34), so that the shoe 46 is slipped smoothly off the last.

I claim:

1. A last removing machine comprising a frame, a last support, movably mounted on said frame, a stripper device movably mounted on said frame, means operable to move said last support towards said stripper device, thereby to apply a lasted shoe on said last support against said stripper device, and means responsive to predetermined contact pressure between the lasted shoe and stripper device to move said stripper device relatively to said frame and said last support.

2. A machine as recited in claim 1 wherein said means operable to move said last support toward said stripper device comprises fiuid-operated means including a cam transmission.

3. A last removing machine as recited in claim 2, wherein said last support comprises an upstanding post fulcrummed in said frame and having, at its lower end, a part movable over a cam surface on an arm mova'ble by said fluid-operated means.

4. A last removing machine comprising a frame, a last support on said frame, a stripper device on said *frame and normally parted from said last support, said stripper device including a part which is yieldable relatively to the remainder, closing means for producing relative movement in a closing direction between the last support and the stripper device, stripper operating means for producing a shoe-slipping movement of said stripper device in a direction transverse to said closing direction, and means responsive to a predetermined yielding of said yieldable part of the stripper device to trigger said stripper operating means.

5. A last removing machine as claimed in claim 4, in which the stripper device comprises an upwardly-movable head assembly, and this assembly includes a stripper member which is pivotably-mounted in the assembly and is adapted to yield and trigger the said stripper operating means.

6. A last removing machine as claimed in claim 4, in which the stripper device comprises a support member, a stripper pad holder hingedly mounted on said support member, compression spring means between said holder and said support member, and switch means operable in response to a predetermined degree of pivoting movement of said holder to trigger said stripper operating means.

7. A last removing machine comprising a frame, a last support pivotable on said frame, a stripper device on said frame and normally parted from said last support, and a pneumatic operating system which comprises a first air cylinder to pivot the last support and cause a lasted shoe on said support to be closed against the stripper device, a second air cylinder to move the stripper device to slip the shoe from the last, a mechanical-lyoperable valve controlling the air supply to said first cylinder, and a solenoid valve operable in response to a predetermined pressure between the shoe and stripper device to open the air supply to said second air cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 2,182,832 Whelton Dec. 12, 1939 FOREIGN PATENTS 735,316 Great Britain Aug. 17, 1955 

1. A LAST REMOVING MACHINE COMPRISING A FRAME, A LAST SUPPORT, MOVABLY MOUNTED ON SAID FRAME, A STRIPPER DEVICE MOVABLY MOUNTED ON SAID FRAME, MEANS OPERABLE TO MOVE SAID LAST SUPPORT TOWARDS SAID STRIPPER DEVICE, THEREBY TO APPLY A LASTED SHOE ON SAID SUPPORT AGAINST SAID STRIPPER DEVICE, AND MEANS RESPONSIVE TO PREDETER- 